| Message ID | 20220409093500.10329-2-linmiaohe@huawei.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | A few cleanup and fixup patches for vmscan | expand |
On Sat, 2022-04-09 at 17:34 +0800, Miaohe Lin wrote: > The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to > follow. Add a comment to make the code clear. > > Suggested-by: Huang, Ying <ying.huang@intel.com> > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> > --- > mm/vmscan.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index c77d5052f230..4a76be47bed1 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1436,6 +1436,9 @@ static void folio_check_dirty_writeback(struct folio > *folio, > /* > * Anonymous pages are not handled by flushers and must be written > * from reclaim context. Do not stall reclaim based on them > + * MADV_FREE anonymous pages are put into inactive file list too. > + * They could be mistakenly treated as file lru. So further anon > + * test is needed. > */ How about something as follows, /* * Anonymous pages (including MADV_FREE ones) are not handled by * flushers and must be written from reclaim context. Do not stall * reclaim based on them */. Best Regards, Huang, Ying > if (!folio_is_file_lru(folio) || > (folio_test_anon(folio) && !folio_test_swapbacked(folio))) {
On Sat, Apr 09, 2022 at 05:34:52PM +0800, Miaohe Lin wrote: > The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to > follow. Add a comment to make the code clear. > > Suggested-by: Huang, Ying <ying.huang@intel.com> > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> > --- > mm/vmscan.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index c77d5052f230..4a76be47bed1 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1436,6 +1436,9 @@ static void folio_check_dirty_writeback(struct folio *folio, > /* > * Anonymous pages are not handled by flushers and must be written > * from reclaim context. Do not stall reclaim based on them While you touch this please add a period at the end of the above sentence. Otherwise looks good: Reviewed-by: Christoph Hellwig <hch@lst.de>
On 2022/4/11 19:50, ying.huang@intel.com wrote: > On Sat, 2022-04-09 at 17:34 +0800, Miaohe Lin wrote: >> The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to >> follow. Add a comment to make the code clear. >> >> Suggested-by: Huang, Ying <ying.huang@intel.com> >> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> >> --- >> mm/vmscan.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/mm/vmscan.c b/mm/vmscan.c >> index c77d5052f230..4a76be47bed1 100644 >> --- a/mm/vmscan.c >> +++ b/mm/vmscan.c >> @@ -1436,6 +1436,9 @@ static void folio_check_dirty_writeback(struct folio >> *folio, >> /* >> * Anonymous pages are not handled by flushers and must be written >> * from reclaim context. Do not stall reclaim based on them >> + * MADV_FREE anonymous pages are put into inactive file list too. >> + * They could be mistakenly treated as file lru. So further anon >> + * test is needed. >> */ > > How about something as follows, > > /* > * Anonymous pages (including MADV_FREE ones) are not handled > by * flushers and must be written from reclaim context. Do not stall > * reclaim based on them > */. > This comment looks good but it seems it doesn't explain the MADV_FREE check logic. Is this already enough? If so, will change to use this. Thanks! > Best Regards, > Huang, Ying > >> if (!folio_is_file_lru(folio) || >> (folio_test_anon(folio) && !folio_test_swapbacked(folio))) { > > > . >
On 2022/4/11 22:16, Christoph Hellwig wrote: > On Sat, Apr 09, 2022 at 05:34:52PM +0800, Miaohe Lin wrote: >> The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to >> follow. Add a comment to make the code clear. >> >> Suggested-by: Huang, Ying <ying.huang@intel.com> >> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> >> --- >> mm/vmscan.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/mm/vmscan.c b/mm/vmscan.c >> index c77d5052f230..4a76be47bed1 100644 >> --- a/mm/vmscan.c >> +++ b/mm/vmscan.c >> @@ -1436,6 +1436,9 @@ static void folio_check_dirty_writeback(struct folio *folio, >> /* >> * Anonymous pages are not handled by flushers and must be written >> * from reclaim context. Do not stall reclaim based on them > > While you touch this please add a period at the end of the above > sentence. Will do. > > Otherwise looks good: > > Reviewed-by: Christoph Hellwig <hch@lst.de> Many thanks for review! > . >
On Sat, Apr 09, 2022 at 05:34:52PM +0800, Miaohe Lin wrote: > The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to > follow. Add a comment to make the code clear. > > Suggested-by: Huang, Ying <ying.huang@intel.com> > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Oscar Salvador <osalvador@suse.de>
diff --git a/mm/vmscan.c b/mm/vmscan.c index c77d5052f230..4a76be47bed1 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1436,6 +1436,9 @@ static void folio_check_dirty_writeback(struct folio *folio, /* * Anonymous pages are not handled by flushers and must be written * from reclaim context. Do not stall reclaim based on them + * MADV_FREE anonymous pages are put into inactive file list too. + * They could be mistakenly treated as file lru. So further anon + * test is needed. */ if (!folio_is_file_lru(folio) || (folio_test_anon(folio) && !folio_test_swapbacked(folio))) {
The MADV_FREE pages check in folio_check_dirty_writeback is a bit hard to follow. Add a comment to make the code clear. Suggested-by: Huang, Ying <ying.huang@intel.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> --- mm/vmscan.c | 3 +++ 1 file changed, 3 insertions(+)